1. Field of the Field
The present invention relates to an air bag device, and more particularly to an air bag device which is used as a device which attenuates an impact to a rider of a motorcycle or the like.
2. Description of Background Art
A jacket has been proposed which incorporates an air inflating chamber (air bag) which is used as a device for attenuating an impact to a rider of a motorcycle or the like. For example, see JP-A-2002-20907 which discloses a jacket provided with an air bag which is deployed to cover the entire body of a rider. Further, Japanese Utility Model Registration publication 3048094 discloses an automatically inflatable vest which includes two air chambers having volumes that are different from each other wherein the two air chambers act to attenuate in two stages.
These conventional jackets adopt a structure wherein the rider and a vehicle body are connected with each other by a wire, and the jacket is configured to detect the elongation of the wire and to deploy the air bag when the rider moves away from the vehicle body and a distance between the rider and the vehicle body exceeds a predetermined value.
Further, JP-A-2002-225673 discloses a driver protection device of a working heavy machine which is configured such that the driver protection device mounts an inclination angle sensor thereof on the vehicle body and deploys an air bag upon determination that a vehicle body falls down when an inclination angle arrives at a predetermined value or more.
The jackets described in JP-A-2002-20907 and Japanese Utility Model Registration Publication 3048094 are configured such that the device is operated when the distance between the rider and the vehicle body becomes larger than a predetermined quantity. Thus, when the rider falls down together with the vehicle body due to a slip or a collision on a side of the vehicle body, a distance between the rider and the vehicle body is not increased. Thus, there exists a possibility that the air bag is not operated.
Further, a driver protection device which is described in JP-A-2002-225673 determines a fall-down of the vehicle body based on only an inclination angle. Thus, when the driver protection device is applied to a motorcycle which travels on a winding road or the like while inclining a vehicle body thereof, there exists a possibility that the air bag is operated depending on a condition of a vehicle-body-inclined traveling (bank traveling). Further, when the vehicle is a motorcycle, there may be a case wherein the inclination angle is increased even when the vehicle is in a handling mode other than a traveling mode. In such a state, there also exists a possibility that the air bag is operated.